Machine for grinding conical surfaces



Feb. 8, 1955 HARTRlDGE MACHINE FOR GRINDING CONICAL SURFACES 2 Sheets-Sheet 1 Filed Sept. 8, 1952 LE3 E HAXTRI'DGE .V

A ttorney Feb. ,8, 1955 L. HARTRIDGE MACHINE FOR GRINDING CONICAL SURFACES 2 Sheets-Sheet 2 Filed Sept. 8, 1952 I Inventor 1.554 /'5 #AXTR/Dei Attorney United States Patehtfi nventiofi' ha's reference'toImprovements infand pumps or injeto'finozizl'e's for, compression ignition enpumpsforgreeeiving such pins or pintles, and the" like;

A "ty 'a ical maehinetowhieh the invention c n be ap-J 1 plie'djfis that",setfoftli-in the specification of British Patent No, 6 57Jl29.

a i ofthejpurpose'speeified' whiehj'is eas'y',andleonyenientztouseFand' p'erm'its articles and work} pie tobei r'apidl'y' ground to Close limits of accuracy he present invention is tofprovide' both' 'inirespfeet to the cone angle (and to the c'onc'entricity 3 ofithe c'oi1edpart. .in relation to a cylindrical body. I

ln aceord e "iththe present invention a machine 'foi-- grinding' conieal surfae's'jon articles or -,wor-kpieees ,in;f,

cludes-a g'uide'i'engag'eablemy a cylindrical part 'ofthe workpieceand a driving belt adapted both'to retain the"- workpi i ithe'yguide during'*'grinding' and to "effect the rotation 7 thei'eofl p 1 Preferablvthe driving belt, is presented to the workk piece in-"su'ch manner'f that not only'fis-the workpiece poner'it of force, is imparted {to the workpi'ece which tends eve it in o'nej direction or 'thefoth'eifagainsta rererg ence' stop; Thusigthe' runlof 't'he beltfat the-pointwhere it 'e'or'n'es into; engagement with, the, jslig'ht dis p v g he ,vvorkpiece 'may be; pone-nee slightly obliquely in*rel"ationto the axis J afo'resaidfaxial eeinppn tis-fg'erie'ra'tedl" 'Theloeating stofp for end'the e I ly -pq y 'r' Pr en edw e workpieceis forced towards; the s'ai' v The aforesaid "guid'e may "conveni oc whe eb t s k ecei ey, I i into pps iti'o' i with the ;driving'f1neniber; rele'asedbu'hof e readily "slipllied engag'ed'pos tign alwhereafter the driving belt 'is brought y it'; tea yj'inserition" otthe workpiece l n; i each base the yielding'inem-E so asflto; press the workpiece yieldi'ri'gly ithfsuffieientftorce to hold it firmly in f the "grinding operation.

In'thefor'egoing.;1thasbeen assumed that the work 2 piefee'ernb'ddies' a cylindrical-"bodyf'surface suitable 'for hayihgfiifeet "driving engag ement -'with a belt "or other equivalent vdriving member and that the workpiece is types of; valv'e pins for the i njector' nozzles or feed pumpsot "compression ignition engines, as well as for grinding laps for lap'ping" the"nozzle" seats of sueh in fefere b going ice 2 eludes the useof such a sleeve surrounding thelworkn piece and which may be secured'in driving engagement? with the'workpiece in any' convenient manner for exam-1' pleby -frictional acting plungers or by grub screws or the like. v

The invention will be hereinafter described as applied:v to re grinding machine of thetchar'acter described. in. the aforesaid patent specificationand referenceswilliherein after he made to the accompanying drawingsiwhereinz Fig. "1 is a planiview basedon thedrawings of vthel1= aforesaid speeification and showing the main working 5 parts thereof embodying thefeature's "of the present in: vention,"

Fig; 2 is an enlarged'vie'w showing the mountingand driving means for the-workpiece in plan, 'the workpiece being located by a stop opposite to the boned-point,

Fig. 3 is an end Iview of Fig. "2, a

Fig. '4is a partialwviewfsimilar to'FigfZ but showing an. arrangement wherein the workpiece is located from a surface portion towards the coned point bf the work piece,-: v e a a Fig.l"'5 is a viewl'asimilar to Fig. 3 but corresponding to Fig. I4 and also showing the drivingtmeniber in the slackenedor released position for permitting'the insersertion and withdrawalof the workpiece.

Fig. 6 is an endjview 'showing the driving of the workpiece inthe' embodiment. according to Fig. 2 the I workpiece being subjected ot an axial component acting towards the stop'and a. I

EigJ 7 is anendfview similar to Fig.6 showing thew arrangement according 'to Fig.-4 withthe belt set to pro vide ani axialcomponent acting towardsconedpoint,

The machine shown hereiri'is applicable to the grinding of components ofor associated with the nozzlesor feed pumps of compress'iodignitiOn engines including laps for 'the yalve or pintle seats in injection nozzles, such components being 'indicatedat' llti The/machine? comprises a suitably' mounted-grinding wheel 55 the drive means for which 'is not s'hown, being 'for ;exam-' ple as described-in the aforesaid'specificationp The base 1 plate of the machine-carries a bottom slide 1 in -turn carrying a cross slide 2, the former being "inount'ed on a saddle 3 fixed to the base plate The" bottom slide 1 is adjustable towards and away from 'thegrinding 1 wheel by means of a feed screwactuated by;meansof 11 an ope'ratingknob 7 carrying graduation markings 8 r'eadable against a suitable index 'mar'king.- The top slide 2 is movable at right angles to the bottom slide "1 by means of a feed screw ope'rableby means of handleba The top slide"2 carries a plate '10 pivotally fmou nted about a bolt- 14 and is slotted at 16 for engagement by Y a screw 15 whereby-the plate 10 may be fixed in angular position. Precise angular adjustment of the plate 10 is etfectedbyme'ans of shale 21 011 the face of the top-slide" and an index rnarking 21a on a bevelled surface portion bf curvedconfiguration on the extremity of the plate 10? Fine' adjustment is obtained by means of ,a finger screw 18 supported by the top-slide 2 on a bracket 19whicli also came's'a dial indicator 23; a -feel'er22 ,l of which engages oneside of the plate 10. It will be realiz'edfthat adjustmentlofthe bottom slidel and top slidef2 and of theangular positioning of the plate lofperrriitscone surfaces of the element 13 to begiven the desired angular. formation and moreover permits said surfaces -'t o" be' pr,e"sented'to the grinding wheel 55 to produce an accurately formed conedtip's'urface which ilsspre'cisely -concentric with'the body of the component The eomponents' under treatment'are supported by, means'fof a work carrier 11 secured to the plate 10 by mean's o ffa boltor stud 37 i The carrier includes a V-grooye 26 (,Figs. "1,2, 3) engageable with the corn ponent '13,' which isjyieldingly. pressed into the -groove by themeans to be described. 7 Thereby the workpiece is. accurately held and by rotation thereofa coned' part "can'jbe groundithereon which is accurately concentric in relationto the body. g I l Figs; and 3 and 6'o n'theone hand; and Figs. 4, Sand 7 .f on thefotherhand show alternative methods "of location of the eompoheiif BbeingQgroundlf' In Figs. 2, 3 and} able stop member 65 secured to the carrier 11 for example by means of carrier block 66 having a U-shaped portion adjustably secured to the forward face of the carrier 11 by means of a clamp screw 67. It will be seen that the stop 65 is engaged by the end of the component 13 opposite to the coned end 131 which is to be ground. The alternative form of component 13 shown on Figs. 4, 5 and 7 is provided with a coned surface 132 adjacent the tip 131, from which surface end location can be effected and it will be appreciated that whereas in Figs. 2, 3 and 6 the component 13 should be urged towards the stop 65 with a movement towards the right, in the case of Figs. 4, 5 and 7 the component 13 should be urged in the opposite direction. For this purpose a stop element 68 is provided in the form of a plate fixed to the side face of the carrier 11 and which is provided with a V-shaped forward part as indicated in Fig. 5 for engagement by the cone surface 132. It will be realized that in this case the component 13 should be urged towards the left hand in order to maintain the surface 132 against the stop 68.

In the construction according to the invention the component 13 is yieldingly urged into the V-groove 26 by means having a driving belt in co-operative engagement with a cylindrical portion of the body of the component 13. As shown in Figs. 1 to 7 the cylindrical body portion of the component is engaged by a flexible belt 70 of circular or wedge section but preferably of circular section and driven by a pulley 71 associated with a drive unit 72 pivotally mounted on an arm 73 extending below the carrier 11, by means of a lever 74 operable to bring the belt into the engaging position shown in Fig. 3 by means of a manipulating handle 75 an angular part of which is adapted, in the position shown in Fig. 3, to engage a suitable notch 76 in the arm 73 so that the lever 74 is retained in the position shown, wherein the belt 70, is pulled against the component 13 so that the latter is held in position in the V-guide 26 and can be rotated when the belt 70 is operated from the pulley 71. The said pulley is journalled in the unit 72 and is rotatably driven by means of a flexible drive shaft 86. Figs. 1 to 4, 6 and 7 show the belt 70 in the driving position while the released position of the belt 70 is shown in Fig. 5 from which it will be seen that the lever 74 has been rocked about the arm 73 so that the belt is slackened and the components 13 can be readily inserted or removed from the V-guide 26.

By means of the structure so far described means are provided for effecting the rotation of the components 13 during grinding but it will be realized that means must be provided also for pressing the components axially against the stops 65 or 68 during the course of the grinding. This axial pressing of the components 13 against the stops is effected by imparting a slight displacement to the driving belt so that it has to pass over the component in a slightly oblique direction. As shown in Figs. 1 to 7 the carrier 11 also supports a rocker plate 77 pivoted on a screw 78 and provided with depending pins 79 adapted to bear against the sides of the belt 70; it being understood that the upper bight of the belt seen in Fig. 2 is travelling towards the component 13 while the lower bight is passing awav from the workpiece. When the rocker plate 77 is shifted clockwise as shown in Fig. 2 it will be seen that the belt. while rotating the component 13, will also produce an axial component tending to move it towards the right and into engagement with the stop 65 and that while the component is being driven it is also held yieldingly against the stop 65 with a substantially constant pressure. The rocker plate 77 is preferably located in its alternative working positions by means of a stop pin 80 on the upper guide 85. hereinafter referred to, said pin 88 projecting into a slot 81 in the plate whereby the rocker plate may be moved from the position shown in Fig. 2 to the alternative position shown in Fig. 4 in which the direction of the axial component is reversed so that the component 13 is subjected to an axial component acting towards the left as required in the case of Fig. 4. These two positions of the belt are moreover clearly shown in Figs. 6 and 7, as seen in end view looking towards the V-guide.

Referring again to the grinding of components 13 having a location surface similar to 132 towards the tip 131 it will be seen that the stop plate 68 is adapted to be fitted when required to the lateral face of the carrier 11 by means of a fixing screw 82 which engages a threaded hole 83 seen in Fig. 3 when the stop plate 68 is to be brought into use. A further knob 84 may be provided on the plate 68 to facilitate manipulation thereof when desired.

Preferably and as shown on Figs. 1 to 5 of the drawings the belt 70 is passed through channelled guides 85 associated with the carrier 11 and on the upper and lower faces thereof so as to protect the belt and to minimize the danger of accidental contact therewith.

Although the use of a V-guide 26 has been referred to herein it will be understood that guides of other shapes may be utilized. Preferably the guides employed are open on the one side to facilitate the insertion and removal of workpieces or components being ground, the insertion and removal of which is made particularly convenient by the arrangement of the invention permitting rapid working to be obtained.

In the use of the machine according to the invention a workpiece to be treated such as a lap for grinding the seating in injector nozzles is placed in the V-guide 26 after releasing the belt 70 by the handle 75. Thereafter the belt is tightened in like manner and rotation of the lap is commenced by operating the flexible drive 86 from a suitable source such as the chuck 59 of the aforesaid specification. The plate 10 is given a correct angular adjustment as necessary by means of the adjusting screw 18, the angle being accurately ascertained from the scale and index 21, 21a with vernier readings obtained from the dial indicator 23. Then the knobs 7 and 6a are appropriately moved to apply the point of the lap being treated suitably to the grinding wheel 55 and the cone tip of the lap is accurately finished while the lap is being rotated by the belt 70 being at the same time forced against the stop 65 or 68 by the inclined positioning of the belt 70 in relation to the lap 13. When grinding is completed the handle 75 is operated to slacken the belt 70, the finished lap removed and a new lap inserted for further treatment.

When necessary the surface of the grinding wheel may be trued by means of a diamond truing tool suitably mounted on the top slide 2.

From the foregoing it will be seen that the belt em braces the shank of the component along a helical segment and its general plane in the zone of engagement is conveniently at about 85 to the axis of the component 13, this angle being at the opposite side of the belt to the conical surface to be ground. The said angle may be adjustable to enable the thrust to be altered to requirements. The zone of engagement of the belt with the component may be about around the axis thereof.

It will be appreciated that because the belt beds the component in one side of the guide 26 the latter may be a simple open V-block and no clamp means (such as 28 described in my said specification) other than the belt, is necessary for effecting the said bedding. The invention is not however limited to the use of a V-block as other types of guide can be used.

Further the necessary deflection of the flights of the belt 70 in the vicinity of the work, in order to produce the helical segmental embrace of the belt with the component may also be effected by making one side of one channel 85 and the diagonally opposite side of the other, at the ends thereof near the component, project towards the general plane of the belt and to contact with the adjacent parts of the respective runs thereof. Such projecting portions or guides may be provided by deforming the appropriate sides of the channels. A part-cylindrical push plate or a pin or pins movable in bodily sense with the driving pulley may then be located immediately in front of the said pulley to ensure that the belt is thrust forward when the pulley is correspondingly moved prior to introducing the work into the machine or removing it therefrom.

The guide 26 for the component being ground may be readily interchangeable for components of different diameters. The drive to the driving unit 72 may be of any suitable kind; the flexible shaft 86 is driven from a power otftake of the grinding wheel drive motor (similar to the chuck 59 of the aforesaid specification).

The parts herein described may be constructed as an attachment unit for an existing grinding machine.

What I claim is:

1. In a machine for grinding conical surfaces on workpieces, a support, a guide on said support and open on one side to locate the workpiece in grinding position from a cylindrical surface portion thereof, a driving element to the workpiece, and stop means on said support to limit endwise movement of the workpiece under said axial component.

2. In a machine for grinding conical surfaces on workpieces, a support, a guide on said support and open on one side to locate a workpiece in grinding position from a smooth cylindrical surface portion thereof, a driving element on said support, a belt partly encircling said driving element and also partly encircling a smooth surface portion of said workpiece thereby to press the workpiece resiliently into said guide and to effect rotation thereof, deflector means located to make contact with one side of one flight of said belt to deflect the said side of the belt adjacent said workpiece to cause the belt to traverse a helical path on a smooth surface portion of the workpiece to impart an axial component of force to the workpiece by movement of the belt, and stop means on said support and engageable by the workpiece by action of said axial component. I

3. A machine according to claim 2 wherein said deflector means comprise a rocker plate on said support and having pins engageable with the belt adjacent the workpiece, and means to limit the amount of the displacement in each direction from the natural position and cause the axial component to be applied to the workpiece in one direction or the other.

4. A machine for grinding conical surfaces on workpieces comprising a machine frame, a grinding wheel and driving means therefor on said frame, a guide on said frame open on one side and adapted to locate the workpiece in the grinding position from a smooth cylindrical surface portion thereof, a driving element, a belt partly encircling said driving element and also partly encircling a smooth portion of said workpiece to press the workpiece resiliently into said guide and to effect rotation thereof, driving means for said belt disposed to position the paths of the belt towards and from the workpiece in different planes to impart an axial component of force to the workpiece, and stop means on said frame engageable by said workpiece by action of said axial component.

5. A machine acording to claim 4 comprising means movably supporting the driving means whereby the driving means is displaceable in relation to the workpiece in order that the axial component of force can be changed according to the nature of the workpiece being treated.

6. A machine for grinding conical surfaces on workpieces comprising a machine frame, a grinding wheel and driving means therefor on said frame, a guide on said frame open on one side to locate the workpiece in the grinding position from a cylindrical surface portion thereof, a driving element, a belt partly encircling said driving element and also encircling a smooth portion of said workpiece in a helical path to press the workpiece resiliently into said guide and to effect rotation thereof and to impart an axial component of force thereto, releasable belt tensioning means on said frame to permit insertion and removal of workpieces, stop means on said frame to limit movement of the workpiece under said axial component.

7. A machine according to claim 6 wherein said belt driving element comprises a belt pulley mounted on a lever and controlled by a manipulating handle including catch means adapted to retain the lever in a position where the belt is pulled tightly against the workpiece and in driving engagement therewith and resiliently pressing the workpiece into the guide.

8. A machine according to claim 7 wherein said belt pulley is journalled in a pulley unit mounted on said lever, said pulleybeing driven by a flexible shaft from a source of power.

9. A machine according to claim 6 wherein the belt is of wedge section.

10. A machine according to claim 6 wherein said belt driving means comprises a driving pulley of conical form. v

11. A machine for grinding conical surfaces on workpieces comprising a machine frame, a sleeve for fitting to a driving element,i-a.belt' jdrivenlbyllsaidiielement and partly encircling said sleeve, deflector ,means locatedjo make.lateral eohtact'with a flight-of said belt to ba lsejthe belt to traversea helical path" to'press the' sleeve rfiesiliently into) said guide, to effect rotation of the woi'kpiecfand fto 'impar'tan axial component offor'ceko the workpiece, and stop means on said frame to limit movement of the workpiece under said axial component.

12. A machine for grinding conical surfaces on workpieces comprising a machine frame, a grinding wheel and driving means therefor on said frame, a guide on said frame open on one side to locate the workpiece in the grinding position from a cylindrical surface portion thereof, a driving element, a belt partly encircling said driving element and also encircling a smooth portion of said workpiece, defiector means located to make lateral contact with a flight of said belt to cause the belt to traverse in a helical path to press the workpiece resiliently into said guide to effect rotation thereof and to impart an axial component of force thereto, and stop means on said frame engageable alternatively by the end of the workpiece and by a step intermediate thereof to limit movement of the workpiece under said axial component.

13. A machine according to claim 12 comprising alternative stop means for engagement by the end of the workpiece or by the intermediate step.

14. A machine according to claim 13 wherein the said stop means engaged by the end of the workpiece is associated with an adjustable carrier and the intermediate comprises a removable member having a V-shaped operative end.

15. A machine for grinding conical surfaces on workpieces comprising a machine frame, a grinding wheel and driving means therefor on said frame, a bottom slide on said frame, a top slide, an angularly adjustable carrier on said top slide, a workpiece guide open on one side mounted on said carrier to locate the workpiece in a grinding position controlled by both said slides and by said carrier, a driving element, a belt partly encircling said driving element and also encircling a smooth portion of said workpiece in a helical path and pressing the workpiece resiliently into said guide to locate said workpiece by a cylindrical surface portion thereof and to effect rotation of the workpiece while grinding is in progress and also to impart an axial component of force thereto, and stop means on said carrier engageable by said workpiece under the action of said axial component.

16. A machine for grinding conical surfaces on workpieces comprising in combination a machine frame, a grinding wheel on said frame, bottom and top slides on said frame and movable in two directions relative to the grinding wheel, an angularly adjustable plate on the top slide, a support block for workpieces mounted on said plate, said block including a V-guide for the workpieces, stop means on said support block engageable by the workpiece, a flexible belt adapted partly to embrace a workpiece in said guide, releasable means for drivingly engaging said belt with a workpiece, means to drive said belt in driving engagement with the workpiece, and means to impart a twist to said belt for the part thereof embracing the workpiece whereby the workpiece is rotated in the guide and simultaneously an axial component of force is imparted thereto to hold it yieldingly against said stop.

17. A machine for grinding conical surfaces on workpieces comprising in combination a support, a grinding wheel, journalled on said support, bottom and top slides on said support and movable in two directions relative to the grinding wheel, an angularly adjustable plate on the top slide, a support block for workpieces mounted on said plate, said block including a V-guide for. the workpieces facing said grinding wheel, alternative stop means on said support block engageable respectively by one end of the workpiece and by a shoulder adjacent the other end thereof, a flexible belt adapted partly to embrace a workpiece in said guide, releasable means for drivingly engaging said belt with a workpiece in said guide, means to drive said bolt in driving engagement with the workpiece, and means to impart a twist in a selected direction to the part of said belt embracing the workpiece, whereby the workpiece is rotated in the guide and simultaneously 7 an axial component of force is imparted thereto to hold 2,121,730 it yieldingly against whichever of said stops is in use. 2,247,994 2,363,448 References Cited in the file of this patent 2,398,250 5 2 607 244 UNITED STATES PATENTS 1,421,205 Fuller June 27, 1922 1,452,508 Hervig Apr. 24, 1923 1,531,281 Garbin Mar. 31, 1925 Nov. 17, 1949 1,909,446 Albertson May 16, 1933 10 8 Cole June 21, 1938 Fiedler July 1, 1941 Siesel Nov. 21, 1944 Robbins Apr. 9, 1946 Cupler Aug. 19, 1952 OTHER REFERENCES Machinery Magazine (British), page 715, volume 75, 

